Gun sighting and ranging mechanism

ABSTRACT

A gun sighting and ranging mechanism in which the operation of ranging the mechanism on the target by the operator automatically adjusts the sights of the gun for precise trajectory compensation at any shooting distance for any bullet. The sighting and ranging mechanism has two separate objective lens systems for focusing two separate images of the target at a common image plane which are viewed through a single eyepiece.

United States Patent 1 1 Hod es 1 Jul 31 1973 GUN SIGHTING AND RANGING 2,107,829 2/1938 Kuppenbender 356 16 MECHANISM FOREIGN PATENTS 0R APPLICATIONS [75] Inventor: Marvin P. Hodges, Penfield, N.Y. 836.590 6,1960 Great Britain [731 Assignees Ranging, lnc., Rochester, NY. [22] Filed: Oct. 26 Primary Examiner-Ronald L. Wibert Assistant ExaminerF. L. Evans [21] Appl. No.: 83,724 Attorney-Stevc W. Grcmban Related US. Application Data [63] Continuation-impart of Ser. No. 755,192, Aug. 26, [57] ABSTRACT 1968, abandoned.

A gun slghting and rangIng mechamsm In whIch the op- 52 us. (:1 356/16, 33/245, 33/276, ranging the mechanism the target by the 356/17 operator automatically adjusts the sights of the gun for 51 1111. C1. F4lg 1/52, GOlC 3/04 Precise l' cmpensatin at any Shooting [58] Field of Search 356/7, 16, 17, 19; any bullet The sighting and ranging mecha- 33/53 R 64 350/33 10 nism has two separate objective lens systems for focusing two separate images of the target at a common [56] References Cited image plane which are viewed through a single eye- UNITED STATES PATENTS 3,123,915 3/1964 Wilkinson 356/21 13 Claims, 22 Drawing Figures 1 -l I 9/ as I L- l I I54 PATENTED 3. 749 .494

SHEET 1 0F 5 AT TORNE Y PATENIEU M31 ma SHEET 2 OF 5 MARVIN F HODGES INVFNTOR A TTORNE Y PAIENIEU mu 3 I ma FIG.9

FIG. l3

PATENTEDJULBIW 3.749.494

SHEET 5 0F 5 INVENTOR. MARVIN P- HODGES ll GUN SIGHTING AND RANGING MECHANISM CROSS-REFERENCE TO RELATED APPLICATION This application is a continuation-impart application of U. S. patent application Ser. No. 755,192, now abandoned entitled Gun Sighting and Ranging Mechanism, filed on Aug. 26, 1968 in the name of Marvin P. Hodges.

BACKGROUND OF THE INVENTION This invention relates generally to sighting mechanisms, and more specifically, to an improved sighting and ranging mechanism for a gun or the like.

Optical sighting mechanisms for guns or the like utilizing a telescopic lens system and cross-hairs are well known in the art. One of such mechanisms requires the operator to make an estimate of the range or distance of the target from the operator, and in response thereto to adjust the sighting mechanism to compensate for the bullets trajectory. Another such mechanism utilizes a rangefinder comprising a beam splitter and mirror for producing two images of a target which are focused by a single objective lens system on an image plane. The images produced by such a system are superimposed, split field images being unattainable, and the image produced by the beam splitter cannot be separately adjusted or focused relative to the other image except for ranging. In this mechanism, the manipulation required to superimpose the images also adjusts the position of the cross-hairs to automatically require tilting of the gun to compensate for the range and trajectory of the bullet. Another prior art mechanism requires an estimate of the size or height of the target. Applicants invention is believed to remove the estimating or guess work involved in the use of such sighting mechanisms by providing a sighting and ranging mechanism which in response to manipulation by the gun operator to superimpose or align in an image plane images of the target viewed through the eyepiece of the mechanism, automatically compensates for the range and trajectory of the bullet used by adjusting the position of the crosshairs relative to the gun barrel in one embodiment, and by displacing the superimposed images a required amount relative to the primary optical axis of the sight scope in another embodiment.

SUMMARY OF THE INVENTION This invention includes within its scope a sighting and ranging mechanism for a gun or the like comprising means such as two separate objective lens systems for focusing two separate images of a target on a common image plane, in which the ranging system of the sighting mechanism is manipulated by the gun operator to superimpose or align the images of the target visible through an eyepiece of the mechanism, such manipulation automatically sighting the gun for the range and predetermined trajectory of the bullet used.

One object of the present invention is to provide a sighting mechanism for a gun or the like having means for producing two separate images of a target on an image plane, each of which may be adjusted or moved relative to the other.

Another object of the invention is to provide a sighting mechanism for a gun for producing an image of the target on an image plane that is displaced relative to a reference line of sight of the sighting mechanism.

Another object of the invention is to provide an improved sighting and ranging mechanism for a gun or the like having two separate objective lens systems which in response to the manipulation of the ranging mechanism for superimposing or aligning images of the target visible through the eyepiece of the mechanism, automatically compensates for the target range and trajectory of the bullet used.

Another object of the invention is to provide an improved sighting and ranging mechanism for a gun or the like that is of simple design and construction, thoroughly reliable and efficient in operation, and economical to manufacture.

Objects and advantages other than those set forth above will be apparent from the following description when read in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings:

FIG. 1 is a front elevational view of a gun on which one embodiment of the sighting and ranging mechanism of this invention is mounted;

FIG. 2 is an enlarged side elevational view of the sighting and ranging mechanism of FIG. 1;

FIG. 3 is a top plan view in section of the sighting and ranging mechanism of FIG. 2;

FIG. 4 is an enlarged segmental view of a portion of the linkage rod disclosed in FIG. 2 and showing an adjustable feature therein;

FIG. 5 is an enlarged top plan view of a control knob of FIG. 1;

FIG. 6 is a side elevational view of the control knob of FIG. 5;

FIG. 7 is a front elevational view of the sighting and ranging mechanism of FIG. 3;

FIG. 8 is a side elevational view in section of another embodiment of the sighting and ranging mechanism of this invention;

FIG. 8A is a segmental view similar to FIG. 8 showing still another embodiment of the invention;

FIG. 9 is an enlarged segmental view in side elevation of the windage plate mounting of the embodiment shown in FIG. 8;

FIG. 10 is an enlarged segmental view in side elevation of the elevation plate mounting of the embodiment shown in FIG. 8;

FIG. 11 is an enlarged segmental view in side elevation of the ranging plate mounting of the embodiment shown in FIG. 8;

FIG. 12 is an enlarged side elevational view of the field of view seen through the eyepiece of FIG. 8 looking at it from line 12-12 and showing two images of a fence out of alignment with one another;

FIG. 13 is a view similar to FIG. 12 showing the images in register or alignment;

FIG. 14 is a schematic side elevational view of a prior art type of sighting scope for a gun;

FIG. 14A is an enlarged view of the field of view of the scope of FIG. 14 showing where the cross-hairs were aimed and where the bullet struck the target;

FIG. 15 is a view similar to FIG. 14 in which the cross-hairs have been shifted downwardly relative to its central position of FIG. 14A;

FIG. 15A is a view similar to FIG. 14A of the field of view of the scope of FIG. 15;

FIG. 16 is a view similar to FIG. 14 in which the image formed by the biscope is shifted or displaced upwardly relative to the cross-hairs;

FIG. 16A is a view similar to FIG. 14A of the field of view of the scope of FIG. 16;

FIG. 17 is a view similar to FIG. 14 in which the biscope is tilted relative to the gun barrel to compensate for range and bullet trajectory; and

FIG. 17A is a view similar to FIG. 14A ofthe field of view of the scope of FIG. 17.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawings, one embodiment of this invention is shown in connection with a gun as seen in FIG. ll. In this embodiment, the sighting and ranging mechanism 112, seen in enlarged form in FIGS. 2 and 3, comprises a lens barrel 14 having a telescopic lens system of any known type comprising a plurality of lens elements 16, a cross-hair, not shown, and a transversely extending housing 18. Housing 18 has a combination mirror-lens system comprising a lens 20 and light refleeting mediums such as mirrors 22, 24 mounted therein to provide, in cooperation with lens barrel 14, a ranging system operating on the well known triangulation principle normally used for determining the range or distance of a target from the operator or mechanism in a manner that is well known in the art. Although housing 18 is shown integrally formed with barrel 14, it may with slight modification be rotatably mounted on barrel 14 for movement between the position shown in FIGS. 2 and 3 for a person who sights with his right eye, to a position 180 removed therefrom (seen dotted in FIG. 3) for the person who sights with his left eye.

The lens barrel I4 is pivotally mounted for movement in the direction of the arrows designated A-A in FIG. 2 on a pivot pin 26 carried by a support 28 secured to the gun barrel 30. The rear of lens barrel 14 has a cam follower plate 32 rigidly secured thereto engageable with a cam member 34. Cam member 34 is pivotally mounted on a pin 36 carried by a support 38 which is adjustably secured to gun barrel 30 for axial movement in the directions designated by the arrows B-B (see FIG. 2). A relatively strong spring 40 encircling pin 26 is interposed between lens barrel l4 and support 28 for strongly urging lens barrel l4 and cam follower plate 32 in a clockwise direction denoted by the arrow A into firm engagement with cam member 34.

A control mechanism is provided for controlling the position of cam member 34 and hence the rotational or elevational position of lens barrel 14 in the direction of the arrows A-A. The control mechanism comprises a rod 42 having one end secured by any suitable means to cam member 34, and its opposite end secured by any suitable means to a rotatable knob 44 as best seen in FIGS. 5 and 6. The knob 44 is rotatably supported by a support member 46 secured to barrel 30 for rotation in the directions designated by the arrows CC' (See FIG. 5) for movement of cam member 34. To provide proper adjustment of rod 42 between cam member 34 and knob 44, rod 42 may be provided in two parts with one of the parts having a threaded portion 48 engageable with a threaded bore 50 in the other part as best seen in FIG. 4. A telescopic linkage 52 transverse to rod 42 has one end connected by any suitable means such as a ball joint to rod 42, and its opposite end secured to a stub shaft 54 extending into and rotatably supported by the offset housing 18 of the sighting mechanism. A mirror control cam 56 (see FIG. 3) is secured to stub shaft 54 and engages a mirror support member 58 which is urged by a spring 60 into engagement with cam 56. Axial movement of rod 42 by means of knob 44 results in pivotal movement of linkage 52, mirror control cam 56, and mirror 22 to permit relative movement of images of the target visible through an eyepiece 62 of telescopic lens barrel 14 for bringing the two images of the target into superimposition. When the images are superimposed, gun barrel 30 will be properly sighted on the target taking into account the target range and trajectory of a predetermined bullet. In order to compensate for bullet trajectory for cartridges of different velocity and weight, cam member 34 is provided with a plurality of openings 54, each of which will permit a slightly different position of cam member 34 for the same position of rod 42 resulting in a slightly different elevational setting in the directions A-A between the sighting and ranging mechanism 12 and gun barrel 30. As indicated earlier, cam member support 38 is also adjustable in the direction of the arrows B-B to permit acceleration of the cam action of cam 34 to compensate for bullet trajectory values of all commercial and military cartridges.

In the embodiment of the invention shown in FIGS. 8-13, optical means are provided for positioning the gun so that it can be accurately sighted on any object or target. In this embodiment, a biscope sighting and ranging mechanism 64 is shown mountable on a gun by any suitable rigid mounting, not shown. A main sight barrel 68 (See FIG. 8) has a primary objective lens system at one end comprising a pair of objective lenses 70, 72 of an effective focal length for forming a focused primary image of a distant object on an image plane I, shown dotted in FIG. 8, within a parallelogram shaped glass prism block 74. The primary image formed at the image plane I by the primary lens system is viewed through an ocular lens 76 secured in an eyepiece 78 at the opposite end of the sight barrel 68. The lenses in the sight barrel 68 have a primary optical axis 0. A reticle 80 such as cross-hairs which provides a point sight P at their intersection is mounted in sight barrel 68 in the focal plane of the ocular lens 76 with the point P" on optical axis 0 which serves as a reference line of sight. A pair of erector lenses 82, 84 are mounted in sight barrel 68 between the reticle 80 and prism block 74 and are movable axially along the optical axis 0 by any suitable linkage, not shown, at different rates to change the power of the scope while maintaining proper focus of an image, as is done in conventional zoom lenses.

A plurality of secondary objective lenses 89, and 91 are mounted in a secondary lens tube 86 integral with a laterally extending housing 88 for forming a secondary image of an object which is reflected from a beveled surface 92 of prism block 74 onto a small rectangular spot of aluminum 94 located on a parallel beveled surface 96 of the prism block 74 at its lower end, which beveled surface 96 is located along the optical axis 0 of the primary objective lenses 70, 72. The prism block 74 is initially ground to make the beveled surfaces 92, 96 parallel to one another, the aluminum spot 94 added, and an end portion 98 of the prism block 74 cemented to the block. The objective lenses 90 have an effective focal length that is substantially equal to the effective focal length of the primary objective lenses 70, 72 for forming a secondary focused image on the image plane I. The secondary image may be only a portion of the primary image to form a split field image as seen in FIGS. 12 and 13, or superimposed image may be achieved by taking the reflective surface 94 out of image plane I. By proper selection of size and position of reflective surface 94, the secondary image can merge into the primary image at the image plane I at any position and at any percentage of the overall field of view. Although a solid glass prism block 74 is used to deflect the secondary image beam to the image plane I and again to the eyepiece 78, any other suitable means such as mirrors or the like may be used. In addition, although two objective lens systems are provided for forming two independent images of a target, other means such as mirror optics involving concave mirrors may be used to form two independent images on a common image plane.

To adjust the biscope 64 for windage any suitable glass plates or lenses W, W (See FIGS. 8 and 9) are adjustably mounted in the objective lens systems for lateral pivotal movement to produce a corresponding lateral shift in the objective lens axis which causes the image to shift laterally with respect to the optical axis of the objective lenses. The plates W, W may be mounted on an apertured support plate 100 pivotal about spherical balls 102 interposed between the plate 100 and a fixed plate 104. The pivoting of the windage plate 100 may be accomplished by any suitable mechanism such as an eccentric cam 106 engageable with an arm 108 on the support plate 100.

Similar elevation plates or lenses E, E are mounted in each of the primary and secondary objective lens systems for properly vertically shifting the optical axis. The windage plates W, W and elevation plates E, E (See FIGS. 8 and are adjusted for accurate firing when the biscope is initially mounted, and once properly adjusted will not require change except to correct subsequent misalignment. The elevation plates E, E are coupled together by any suitable linkage mechanism such as cams, gears or screws for synchronous pivotal movement of the plates for vertically shifting the primary and secondary images with respect to the optical axes of the objective systems. A mechanism for accomplishing this comprises an apertured fixed plate 110 to which the elevation plates E, E are pivotally mounted on spherical balls 112. The plates E, E are moved synchronously by a knob 114 having an arm 116 secured thereto with a pin 118 at one end movable in a slot 120 in plate 122. The ends of plate 122 are pivotally secured to arms 124 secured to plates E, E. The plates E, E may be adjusted relative to one another by adjusting eccentric screw 126 if necessary to correct any vertical misalignment between the two axes.

In addition, ranging plates or lenses R, R (See FIGS. 8 and 11) are adjustably mounted in each of the primary and secondary objective lens systems and actuated by a cam system so that when the two images of a target at any predetermined range are aligned or superimposed at image plane I (See FIG. 13) the point sight of the cross-hair 80 accurately predicts the point of impact of the bullet at that range, accounting for the trajectory drop, provided eccentric cam 146 has been rotated on axis B-C to present to cam follower 144 the cam face which is appropriate for the particular gun- /ammunition combination in use.

To accomplish this, the ranging plates R, R as best seen in FIG. 11, are pivotally mounted on spherical balls 128 in a similar manner to the elevation plates E, E and differentially pivoted. Fixed arms 142 on plates R, R are biased by any suitable means, not shown, against discs 138, 140 on shaft 136, and because surface 141 has a different rise than surface 139 (or no rise), plates R, R are moved different amounts as shaft 136 is rotated by knob 143. Shaft 136 is caused to move axially as it is rotated by cam follower arm 144 riding along the surface of cam 146. As cam 146 is rotated about its axis B-C, different cam surfaces are presented to cam follower 144 to compensate for various trajectories which result from different gun/ammunition combinations.

The limiting accuracy of the instrument is a function of the magnification and the separation between optical axes, or ranging base length. It is convenient to make the base length short, and then to optically extend it with a periscope box 148 into which light enters through opening 149. If the parallelism of the mirrors 150, 152 (or lack of it) only remains constant, the position and orientation of the box relative to the rest of the instrument is very much less critical than the parts of the main instrument. Thus it may be conveniently demountable, or folded down about pivotal shaft 154 as shown dotted in FIG. 8. Further, boxes of different length may be mounted interchangeably, enabling the ranging operation to be performed at greater or lesser distances, provided only that a range scale appropriate for the base length used be attached to the range knob or the instrument body.

In the embodiment of the invention shown in FIG. 8, the elevation, windage and ranging plates are all positioned between image plane I and lens 70. Accordingly, when the ranging plates R, R are adjusted to range in on a target, the two images formed at the image plane I are automatically shifted or displaced upwardly from optical axis 0 to automatically compensate for the range and trajectory of the bullet. Consequently, when the point P of the cross-hairs is sighted on a point on the target visible in the image plane, the bullet will accurately strike that point of the target. In the embodiment of the invention shown in FIG. 8A, only one ranging plate R" is positioned in the secondary lens system, and elevation and windage plates E, E, W are positioned between the image plane I and the eyepiece 78. Elevation plate E is adjusted for accurate firing when the scope is initially mounted, and once properly adjusted is fixed in that position. During ranging, the two plates R, E are cammed together for simultaneous differential movement, and the images at image plane I are not displaced from optical axis 0", such displacement occurring between image plane I and the cross-hairs due to the action of the elevation plate E.

With reference to FIGS. 14 17, FIG. 14 schematically illustrates a prior art telescopic rifle sight 156 mounted on a gun barrel 30. With such a sight, if the point P of the cross-hairs of the scope is sighted on a target Y (barrel 30 pointing directly at Y), a bullet fired will, depending upon its trajectory, strike the target at Z. Assuming the scope were powerful enough, the field of view would appear as seen in FIG. 14A with point P in register with target image Y and Z indicating the impact point Z of the bullet. With this type of scope, to hit the target Y, it is necessary to place the point P of the cross-hairs on an imaginary target an estimated distance above target Y to compensate for the bullet drop. The same result may be achieved as seen in FIGS. 15 and 15A by changing the cross-hairs 80 so that the intersection point P is in register with the image Z of the impact point Z. With this arrangement, the point P is centered on impact point Z, and since barrel 30 is still pointing at target Y, the bullet will drop and strike impact point Z. In FIGS. 16 and 16A, a biscope 64 of the type shown in FIG. 8A is mounted on gun barrel 30 having the deflection plate E for shifting or displacing registered images of the target relative to the primary optical axis 0. When the point P of the cross-hairs is aligned with impact point image Z, the barrel 30 is pointing at target Y and the bullet will accurately strike impact point Z. FIGS. 17 and 17A show a scope arrangement similar to the embodiment of the invention shown in FIGS. 1 7 in which the cam 34 is interposed between the scope l2 and gun barrel 30. With this arrangement, scope 12 has been ranged on target Y, and since the ranging function is coupled to cam 34, the cam is moved the required amount tilting the scope relative to the barrel. Now if the scope is aimed at impact point Z by centering point P of the cross-hairs on impact point image Z as seen in FIG. 17A, the barrel 30 will be pointing at target Y and the bullet fired will drop and strike the impact point Z.

The invention has been described in detail with particular reference to a preferred embodiment thereof, but it wil be understood that variations and modifications cal) be effected within the spirit and scope of the inventio as described hereinabove, and as defined in the appended claims.

I claim:

1. In a sighting and ranging mechanism for a gun, the combination comprising:

a sight scope mountable on a barrel of a gun, said scope having optical means defining an optical axis forming a substantially fixed reference line of sight, an image plane transverse to said optical axis onto which an image of the target is formed, and a point sight adapted to be visually aligned with any part of said image for sighting the gun on the target; and image moving means for substantially simultaneously determining the range of the target and vertically displacing the target image from said reference line of sight an amount sufficient to compensate for the range of the target and the trajectory of the bullet.

2. The invention according to claim 1 wherein said image moving means comprises an image displacing means interposed between said image plane and said point sight.

3. The invention according to claim 2 wherein said image displacing means comprises a pivotally mounted elevation plate.

4. In a sighting and ranging mechanism for a gun having a primary objective lens defining an optical axis, an image plane transverse to said optical axis and a point sight which when aligned with a reference point on said image plane at said optical axis forms a substantially fixed reference line of sight along which a target is sighted, the combination comprising:

means for forming a pair of independent images of a target on said image plane; and

image moving means for substantially simultaneously moving said pair of images into register and vertically displacing said registered images from said reference line of sight a predetermined amount to compensate for the range of the target and the trajectory of a bullet. 5. The invention according to claim 4 wherein said image moving means comprises an image displacement means interposed between said image plane and said point sight for displacing the registered images.

6. The invention according to claim 5 wherein said image displacement means comprises a pivotally mounted elevation plate.

7. In a biscope sighting and ranging mechanism for a gun, the combination comprising:

sighting means mountable on to a barrel of the gun and having optical means having a primary optical axis, an image plane transverse to said optical axis and a point sight which when aligned with a reference point on said image plane at said optical axis forms a substantially fixed reference line of sight;

first optical means for forming a first image of a target on said image plane;

second optical means optically coupled to said first optical means for forming a second image of the target independent of said first image on said image plane; and

image moving means coupling said first and second optical means for substantially simultaneously moving said first and second images on said image plane into register and vertically displacing said registered images from said reference line of sight an amount dependent upon the distance to the target and the trajectory of the bullet such that when said point sight is sighted on a spot on said registered images, the gun barrel is pointed at a place on the target above said spot on said registered images so that a bullet fired from the gun will strike a corresponding spot on the target.

8. The invention according to claim 7 wherein said second optical means has an image deflecting element optically connecting said second optical means to said first optical means.

9. The invention according to claim 7 wherein said second optical means has an image deflecting element comprising a parallelogram shaped prism optically connecting said second optical means to said first optical means. I 3

10. The invention according to claim 7 wherein said second optical means has an image deflecting element comprising a parallelogram shaped glass prism optically connecting said second optical means to said first optical means, said image plane being formed in said prism along the optical axis of said first optical means.

11. The invention according to claim 7 wherein said second optical means has an image deflecting element optically connecting said second optical means to said first optical means, and a third portion extending transversely from said second optical means for collecting light from the subject and introducing the light into said second optical means. I

12. The invention according to claim 11 wherein said third portion is pivotally mounted on said second optical means.

13. The invention according to claim 7 in which said image moving means comprises at least one image deflecting plate responsive to said image moving means :for displacing said images from said reference line of sight. 

1. In a sighting and ranging mechanism for a gun, the combination comprising: a sight scope mountable on a barrel of a gun, said scope having optical means defining an optical axis forming a substantially fixed reference line of sight, an image plane transverse to said optical axis onto which an image of the target is formed, and a point sight adapted to be visually aligned with any part of said image for sighting the gun on the target; and image moving means for substantially simultaneously determining the range of the target and vertically displacing the target image from said reference line of sight an amount sufficieNt to compensate for the range of the target and the trajectory of the bullet.
 2. The invention according to claim 1 wherein said image moving means comprises an image displacing means interposed between said image plane and said point sight.
 3. The invention according to claim 2 wherein said image displacing means comprises a pivotally mounted elevation plate.
 4. In a sighting and ranging mechanism for a gun having a primary objective lens defining an optical axis, an image plane transverse to said optical axis and a point sight which when aligned with a reference point on said image plane at said optical axis forms a substantially fixed reference line of sight along which a target is sighted, the combination comprising: means for forming a pair of independent images of a target on said image plane; and image moving means for substantially simultaneously moving said pair of images into register and vertically displacing said registered images from said reference line of sight a predetermined amount to compensate for the range of the target and the trajectory of a bullet.
 5. The invention according to claim 4 wherein said image moving means comprises an image displacement means interposed between said image plane and said point sight for displacing the registered images.
 6. The invention according to claim 5 wherein said image displacement means comprises a pivotally mounted elevation plate.
 7. In a biscope sighting and ranging mechanism for a gun, the combination comprising: sighting means mountable on to a barrel of the gun and having optical means having a primary optical axis, an image plane transverse to said optical axis and a point sight which when aligned with a reference point on said image plane at said optical axis forms a substantially fixed reference line of sight; first optical means for forming a first image of a target on said image plane; second optical means optically coupled to said first optical means for forming a second image of the target independent of said first image on said image plane; and image moving means coupling said first and second optical means for substantially simultaneously moving said first and second images on said image plane into register and vertically displacing said registered images from said reference line of sight an amount dependent upon the distance to the target and the trajectory of the bullet such that when said point sight is sighted on a spot on said registered images, the gun barrel is pointed at a place on the target above said spot on said registered images so that a bullet fired from the gun will strike a corresponding spot on the target.
 8. The invention according to claim 7 wherein said second optical means has an image deflecting element optically connecting said second optical means to said first optical means.
 9. The invention according to claim 7 wherein said second optical means has an image deflecting element comprising a parallelogram shaped prism optically connecting said second optical means to said first optical means.
 10. The invention according to claim 7 wherein said second optical means has an image deflecting element comprising a parallelogram shaped glass prism optically connecting said second optical means to said first optical means, said image plane being formed in said prism along the optical axis of said first optical means.
 11. The invention according to claim 7 wherein said second optical means has an image deflecting element optically connecting said second optical means to said first optical means, and a third portion extending transversely from said second optical means for collecting light from the subject and introducing the light into said second optical means.
 12. The invention according to claim 11 wherein said third portion is pivotally mounted on said second optical means.
 13. The invention according to claim 7 in which said image moving means comprises at least one image deflecting plate responsive to said image moving meaNs for displacing said images from said reference line of sight. 